Radiation Hydrodynamic Simulations of Massive Stars with Rotation

PI Name: 
Lars Bildsten
Institution: 
University of California, Santa Barbara
Allocation Program: 
INCITE
Allocation Hours at ALCF: 
1.3 Million
Year: 
2019
Research Domain: 
Physics

Massive stars play an important role in many astrophysical environments. Along with supernovae, they produce the majority of the heavy elements in nature, seeding the universe with the ashes of nuclear burning from which planets form and life is made.

While previous INCITE research—including recent global radiation hydrodynamic simulations that indicated the importance of helium opacity peak to outbursts of Luminous Blue Variables—has improved our understanding of massive stars’ behavior, many of their puzzles remain unsolved.

This project executes three-dimensional global radiation hydrodynamic simulations of Wolf-Rayet star envelopes by directly solving the time-dependent radiation transfer equation along discrete rays. These simulations will resolve the convection developed around the iron opacity bump region due to the super-Eddington radiation flux and probe the mechanism to drive the large mass loss rate for these stars. 

By coupling the rotation, convection, and three-dimensional radiative transfer self-consistently, the researchers will also carry out the first sets of simulations to study the effects of rotation on the envelope structures and mass loss. The results will be incorporated into one-dimensional stellar evolution models to create more realistic massive star models and supernovae progenitors, which will significantly improve our understanding of the structures and evolutions of massive stars.